Sending arrangement



July 27, 1926. 1,593,662

A. MEISSNER SENDING ARRANGEMENT Filed Sept. 5, 1921 am/U014 toz H1: E X FINDER Nf/JQSNf/T 33 h" elf tome l i Patented July 27, 1926.

UNITED STATEEi ATENT OFFICE.

ALEXANDER MEISSNER, OF BERLIN, GERMANY, ASSIG-NOR TO GESELLSOHAFT FIIR DRAHTLOSE TELEGRAPHIE M. B. H. HALLESCHES, OF BERLIN, GERMANY, A COR- PORATION OF GERMANY.

SENDING ARRANGEMENT.

Application filed September 3, 1921, Serial No. 498,419, and in Germany September 26, 1918.

(GRANTED UNDER THE PRGVISIONS QF THE ACT 62? MARCH 3, 191 L1 STAT. L, 1313.)

German Patent 304361 discloses a sender arrangement in which special means are provided for preventing the radiation of harmonics produced in the generator. The main patent refers to the case of a cathode tube sender in which the harmonics have particularly disturbing efieets if the antenna as an energized circuit is connected direct with the tubes. Practical experience has shown that all other generators of undamp ed oscillations, such as are lamps, high frequency machines, etc, send out harmonics through known circuits and cause disturbances in the modern, highly sensitive receiving arrangements.

In accordance with the invention, the special protecting circuits disclosed in the main patent are applied also to such gener ators. The arrangement is applicable to circuits in which the generator is connected direct with the main circuit (antenna), and also to circuits in which the generator affects an alternating current resistance provided in the main circuit (antenna).

Figs. 1, 2 and 3 of the drawing represent such circuit arrangements, in which a protecting circuit S tuned to the main oscillation is connected in parallel with the an tenna. The generator, are lamp, or high frequency machine is connected at G.

This simple arrangement for preventing the radiation of undesirable harmonies is particularly advantageous. The trap S has practically an infinite impedance to the main or carrier frequency and almost as great impedanees to the side band frequen cies which, of course, are always close to the carrier frequency.

Thus the carrier and side band frequen cies will be transmitted while the undesin able frequencies which are quite different from the carrier frequency will find a comparatively easy path thru the trap S and hence will not be transmitted.

Having described my invention, I claim:

1. In a radio transmitting apparatus, an antenna system, a source of a plurality of frequencies coupled thereto and means for absorbing oscillations it is desired not to transmit comprising solely a trap for the oscillations it is desired to transmit and means for coupling said trap directly to said antenna system.

2. In a transmitting apparatus, an antenna system, a source of a plurality of fre quencies coupled thereto, and means for absorbing the frequencies it is desired not to transmit comprising a circuit having a high impedance for the frequency it is desired to transmit, the impedance of said circuit for other frequencies gradually decreasing with increase in the difference in frequency from the frequency it is desired to transmit and means for connecting said absorbing means directly to said antenna system.

In testimony whereof I affix the signature.

ALEXANDER MEISSNER. 

